MACF1与成骨细胞骨架之间的相互关系研究

采用激光共聚焦显微术研究微管微丝交联因子（MACF1）与成骨样细胞（MD63及MC3T3）微丝／微管骨架、黏着斑之间的相互关系．结果表明,MACF1不连续地分布于微管纤维上,与微丝骨架部分共定位于胞质中,在很多的成骨细胞中可见MACF1分布于骨架相关的粘着斑处：细胞松弛素B影响了MACF1在成骨细胞中的分布,并有使其向细胞核周围及核内转位的趋势．秋水仙素对MACF1的分布无明显的影响．转染了siRNA—MACFl的MG．63细胞微丝骨架纤维分布不连续、微管骨架纤维分布紊乱．这些结果提示MACF1不仅起交联微丝及微管细胞骨架的作用．而且还可稳定细胞骨架：成骨细胞MACF1的分布更依赖于微丝骨架的完整性．

Association of Microtubule Actin Crosslinking Factor 1 with Cytoskeleton in Osteoblast

The association of microtubule actin crosslinking factor 1 (MACF1) with actin filaments (Afs), microtubule (MT) and focal adhesion were examined using laser scanning confocal microscopy (LSCM). Results showed that MACF1 aligned along MT filaments and partly co-localized with the Afs and MT in the Cytoplasm. In many osteoblast, anti-MACFl labeling could be found in regions of focal adhesions, cytochalasin B caused translocation of MACF1 to the perinuclear region or nucleus, in contrast, colchicines had no obvious effects on the association of MACF1 with cytoskeleton. Afs were discrete and disrupted, and MTs were disorganized in MG-63 cells tranfected with siRNA-MACFl compared with that in control cells. These results indicate that MACF1 plays an important role not only in linking cytoskeleton proteins but in stabilizing the cytoskeleton structure. The association of MACF1 with cytoskeleton primarily depends on the integrity of the actin network.